[MAPREDUCE-199] Locality hints for Reduce

• Type: New Feature
• Status: Reopened
• Priority: Major
• Resolution: Unresolved
• Component/s: applicationmaster, mrv2
• Assignee: Unassigned
• Reporter: Benjamin Reed
• Created: 10/Oct/06 14:21
• Updated: 26/Oct/16 14:49

Description

It would be nice if we could add method to OutputFormat that would allow a job to indicate where a reducer for a given partition should should run. This is similar to the getSplits() method on InputFormat. In our application the reducer is using other data in addition to the map outputs during processing and data accesses could be made more efficient if the JobTracker scheduled the reducers to run on specific hosts.

Issue Links

• blocks: HBASE-1199 TableMapReduceUtil.initTableReduceJob smart reduce assigned to server hosting region